This invention relates to a device to extract juice from vegetables and fruits, using a strainer basket, driven by a motor-powered, vertically rotating shaft, and a grating disc, which is located at a certain distance from the outlet of a feeder cylinder, mounted eccentrically to the power-driven pivot and rotating together with the strainer basket.
Prior art juice extraction devices function in such a way that the fruit and vegetable parts are grated by the grating disc which rotates at a short distance from the outlet of the feeder cylinder. Then the grated particles are forced by centrifugal force against the walls of the strainer basket, whereby the juice is separated from the pulp in the basket. Due to the non-continuous feeding of the fruit or vegetable parts, the possibility of an uneven distribution of particles along the inner wall of the strainer basket exists and can result in a high degree of unbalance in the quickly rotating strainer basket, which in turn will produce vibrations of the entire device, forcing the user to turn off the motor and to empty the strainer basket, although it has not yet reached its maximum capacity.
To eliminate this occurrence of an unbalance, several different constructions have been suggested, all of which must be considered to be too complex to be practical, or they contain parts that are submitted to excessive wear and tear. This is the case, for example, in such a device in which the grating disc is not connected tightly with the power-driven strainer basket. It is driven by friction in such a way that the grating disc can altar its position in relation to the strainer basket when an unbalance occurs. The lag created by the frictional drive varies greatly for the different products to be processed and therefore necessitates further measures to overcome these difficulties.
Another well-known device uses an elastic connection between the drive shaft and the strainer basket, each linked by a coupling part. This drive connection consists of five elastic joints, arranged in a circle, which could be spring elements for example, and allow the strainer basket to be tilted out of its coaxial position in relation to the power drive, so that in case of an unbalance the strainer basket can adjust itself to a somewhat inclined position. Thus the distance between the outlet of the feeder cylinder and the sector neighboring the unbalanced part of the strainer basket will be enlarged and less of the feeding material will be grated. This will now re-establish an even distribution within the strainer basket, whereby the elasticity of the coupling attempts to align the symmetrical axis of the grating disc and the strainer basket into an axial alignment with the power drive.